The Cysteine-to-Histidine Substitution in b
Domain of Metallothionein Enhances its Zinc Binding Ability. Pp. 9-16.
Yanjiao Zhou, Ning Zhang, Lingyuan Li and Binggen Ru
[Abstract]
Amino Acid Sequence and Molecular Modeling of a Lipid Transfer Protein
from the Seeds of Prosopis juliflora and its Interaction with Palmitic
Acid. Pp. 17-24.
André Newton Monte Negreiros, Artur Torres Cordeiro and Carlos
Bloch Jr.
[Abstract]
Expression, Purification, Crystallization and Prelirninary X-ray Analysis
of the Augmenter of Liver Regeneration. Pp. 25-32.
Chia-Kuei Wu, Tamara A. Dailey, Harry A. Dailey, Antonio Francavilla,
Thomas E. Starzl, Bi-Cheng Wang and John P. Rose
[Abstract]
Wolff Rearrangement of Na-Protected
a-Aminodiazoketones in Presence of Substituted
Phenol as a Method for the Synthesis of 2,4,5-Trichlorophenyl Esters of
Fmoc-/Boc-/Z-b-Homoamino Acids. Pp. 33-36.
Hosahudya N. Gopi, Kuppanna Ananda and Vommina V. Suresh Babu
[Abstract]
Cytotoxicity and Membrane Perturbation Associated with the Myristylated
N-Terminal Protein of HIV-1 GAG Protein. Pp. 37-42.
C. C. Curtain and I.G. Macreadie
[Abstract]
The Specificity of Enteropeptidase Relative to the Chimeric Proteins
and Trypsinogen Processing. Pp. 43-48.
Elena Shibanova, Sergey Alexandrov and Anatolii Miroshnikov
[Abstract]
Human Nucleotide Excision Repair Protein XPA: Summary of EXAFS Studies
on the Zn (II), Co (II) and Cd (II) Associated Minimal DNA-Binding Domain.
Pp. 49-56.
Garry W. Buchko, Nancy J. Hess and Michael A. Kennedy
[Abstract]
Equilibrium Unfolding of Yeast Triosephosphate isomerase: A Monomeric
Intermediate in Guanidine-HCl and Two-State Behavior in Urea. Pp. 57-64.
Edgar Vázquez-Contreras, Rafael A. Zubillaga, Guillermo Mendoza-Hernández,
Miguel Costas and D. Alejandro Fernández-Velasco
[Abstract]
[Back to top] The Cysteine-to-Histidine
Substitution in b Domain of Metallothionein
Enhances its Zinc Binding Ability. Yanjiao Zhou, Ning Zhang, Lingyuan Li
and Binggen Ru.
A two-step PCR method was taken to replace the cysteines at position
19, 29 in b domain of Metallothionein with histidines.
Then the His19,29-mutant fragment was cloned into the vector
pGEX-4T-l and expressed as a fusion protein of glutathione-S-transferase.
After cleaved with thrombin and purified, the b
domain with the substitution of Cys-to-His was obtained and identified
by amino acid composition and molecular weight. The His19,29
mutant can bind with the same amount of zinc or cadmium ions as the b
domain but exhibits stronger zinc binding ability and weaker cadmium binding
ability.
[Back to top] Amino Acid
Sequence and Molecular Modeling of a Lipid Transfer Protein from the Seeds
of Prosopis juliflora and its Interaction with Palmitic Acid. André
Newton Monte Negreiros, Artur Torres Cordeiro and Carlos Bloch Jr.
A basic, ninety two arnino acid residue polypeptide, called CM4-3,
was purified from seeds of Prosopis juliflora and sequenced. Sequence
homology searches indicated that this protein is related to the nonspecific
lipid transfer protein farnily (ns-LTP). A 3D model of CM4-3 was built
base on the molecular coordinates of a maize ns-LTP and the obtained model
revealed the presence of a highly conserved pocket formed by three a-helices
capable of accommodating one molecule of palmitic acid inside the CM4-3
structure.
[Back to top] Expression,
Purification, Crystallization and Preliminary X-ray Analysis of the Augmenter
of Liver Regeneration. Chia-Kuei Wu, Tamara A. Dailey, Harry A. Dailey,
Antonio Francavilla, Thomas E. Starzl, Bi-Cheng Wang and John P. Rose.
A novel growth factor termed augmenter of liver regeneration (ALR)
c~ntaining an N-terminal histidine tag has been expressed, purified and
crystallized. The crystals diffract to beyond 2 Å, belong to space
group I41 with a = 99.8Å and c = 113.4Å, and have
four molecules per asymmetric unit. Cadmium proved essential to the crystallization
of the protein and the positions of four cadmium atoms have been determined
by Bijvoet difference Patterson analysis. A possible role for cadmium stabilization
of the his-tagged protein lattice is discussed.
[Back to top] Wolff Rearrangement
of Na-Protected a-Aminodiazoketones
in Presence of Substituted Phenol as a Method for the Synthesis of 2,4,5-Trichlorophenyl
Esters of Fmoc-/Boc-/Z-b-Homoamino Acids. Hosahudya
N. Gopi, Kuppanna Ananda and Vommina V. Suresh Babu.
Silver acetate catalyzed decomposition of the Na-Protected
a-Aminodiazoketones in the presence of 'substituted
phenol' and triethylamine at -15°C lead to 2,4,5-trichlorophenyl esters
of Fmoc-/Boc-/Z-b-homoamino acids in good yield
and purity. Thus the homologation of a-amino
acids to b-homoamino acids with concomitant
active esters formation has been achieved by this method.
[Back to top] Cytotoxicity
and Membrane Perturbation Associated with the Myristylated N-Terminal Protein
of HIV-1 GAG Protein. C. C. Curtain and I.G. Macreadie.
The Gag and Nef proteins of human immunodeficiency type 1 (HIV- 1)
have conserved N-terminal sequences that appear essential for HIV-1 function.
In view of the structural similarities a Gag peptide corresponding to myrGag2-22,
was subjected to cytotoxicity tests employing recently developed cell assays.
The Gag peptide displays a similar activity to Nef. The role of such sequences
may be important in viral membrane association, viral biogenesis and transition
of these proteins through the cellular membrane.
[Back to top] The Specificity
of Enteropeptidase Relative to the Chimeric Proteins and Trypsinogen Processing.
Elena Shibanova, Sergey Alexandrov and Anatolii Miroshnikov.
The limited proteolysis by enteropeptidase of the recombinant chimeric
proteins incorporating the linker (Asp)4-Lys was studied. The
resistant to the hydrolysis chimeric proteins was shown to be the competitive
inhibitors in relation to the effectively splitting chimeric proteins and
to the low molecular intermediates of the linker, but not of the trypsinogen
processing. The linker was shown to be defined the binding of the protein
substrates by enzyme only, rather than the efficiency, determined by the
C-terminal component of enzyme specificity.
[Back to top] Human Nucleotide
Excision Repair Protein XPA: Summary of EXAFS Studies on the Zn (II), Co
(II) and Cd (II) Associated Minimal DNA-Binding Domain. Garry W. Buchko,
Nancy J. Hess and Michael A. Kennedy.
The zinc in the metal-binding core of the DNA-binding domain of the
nucleotide excision repair protein XPA (M98-F219) can be replaced with
cadmium (II) and cobalt (II). Here, we summarize extended X-ray fine structure
spectra collected on each protein in the lyophilized state and in 15% frozen
aqueous glycerol solution. Under both conditions the Zn2+, Cd2+,
and Co2+ are tetrahedrally coordinated to the sulfur atom of
four cysteine residues with the Zn-S and Co-S bond lengths nearly identical,
at 2.34 Å, and the Cd-S bond length at 2.54 Å.
[Back to top] Equilibrium
Unfolding of Yeast Triosephosphate isomerase: A Monomeric Intermediate
in Guanidine-HCl and Two-State Behavior in Urea. Edgar Vázquez-Contreras,
Rafael A. Zubillaga, Guillermo Mendoza-Hernández, Miguel Costas
and D. Alejandro Fernández-Velasco.
This is the first experimental evidence of an equilibrium intermediate
in the unfolding of triosephosphate isomerase (TIM). The reversible unfolding
of S. cerevisiae TIM induced by both guanidine-HCl (Gdn-HCI) and
urea, are apparently monophasic when followed by spectroscopic techniques.
Kinetic analysis and ANS binding data confirm a two-state transition in
urea, nevertheless, in Gdn-HCI they indicate an intermediate. Hydrodynamic
properties of the intermediate are consistent with a compact monomer.